<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>JavaScript</title>
		<script>
			function lin1(){
				document.write("i am  been clicked");
				var i =123;
			     alert(i);
			var j= prompt(" please input");
			alert(typeof j);//检测数据类型
			}
// 	  var  a = 1;
// 	   var b ;
// 	    b=a++;
// 		alert("b="+b+"a="+a);

  /*  var b ="abc123";
	  b = parseInt(b);
	    alert(b); */
		
	/* 	var a = "6"
		a= Boolean(a);
		alert(a); */
		
		</script>
	</head>
	
	<body>
		<input type="button" value=" click me "  onclick=" lin1()"/>
	</body>
</html>
